A common operation on many worksites is the excavation and removal of material. For example, in open-cut mines, material is excavated from a certain location and loaded into trucks for transport to a designated dumping location. Loading machines, such as electric mining shovels or excavators, are commonly used to load the trucks with material. Loading machines collect material in a bucket and deliver it to the bed of the truck, which will usually have the capacity for multiple bucket-loads of material.
Monitoring the work cycles of the truck and/or the loading machine can be useful. For example, a worksite operator may want to monitor the number of work cycles completed in a workday to assess productivity, the amount of revenue generated, the amount of inventory moved, or other parameters.
Some operators, such as operators of large worksites, can afford high-end trucks and loading machines equipped with sensors that support systems for monitoring work cycles. For example, some high-end trucks have a payload sensor that measures the weight of the payload in the truck bed, a bed sensor that senses whether the bed is raised or lowered, a gear sensor that senses the gear in which the truck is operating, and/or a ground speed sensor that measures the ground speed of the truck. High-end loading machines may have similar sensors, as well as a bucket sensor configured to sense the height or angle of the bucket. Using the information provided by these sophisticated sensors, work cycles or phases thereof can be determined.
One example of such a system is disclosed in U.S. Pat. No. 8,364,440 to Putkonen (“the '440 patent”). In the system described in the '440 patent, a loading machine is equipped with sensors that monitor the signals of the control stick, including speed, direction, and tool state. The loading machine also has a sensor that measures the weight of the payload in the bucket. The '440 patent system applies a mathematical model to the information provided by these sensors to determine the work cycle and state of the loading machine.
While the system of the '440 patent may assist worksite operators in assessing productivity, it may have certain drawbacks. For example, the equipment needed to implement the monitoring of the '440 patent may be too expensive for operators of smaller worksites, such as coal mines and quarries. And even operators of larger worksites may want to avoid purchasing expensive equipment for monitoring work cycles. Accordingly, a less expensive solution is needed.
This disclosure is directed to overcoming one or more of the problems set forth above and other problems in the art.